7? ? 

 OUR KNOWLEDGE OF 

 THE EXTERNAL WORLD 



AS A FIELD FOR SCIENTIFIC METHOD 



IN PHILOSOPHY 



BY 



BERTRAND RUSSELL, M.A., F.R.S. 



LECTURER AND LATE FELLOW OF TRINITY COLLEGE, CAMBRIDGE 



FOURTH THOUSAND. 



THE OPEN COURT PUBLISHING COMPANY 



CHICAGO AND LONDON 

 1915 



